The present invention relates to a device for inspecting small pharmaceutical products such as tablets or capsules.
Important functions which are to be performed when bottles or other containers are being filled with tablets or capsules are to count the tablets or capsules and to sort out the defective ones. Commercially available systems work with different technologies.
Color cameras can detect incorrectly colored or broken tablets or capsules by appropriate evaluation of the images. Because of the continuous movement of the tablets or capsules past the camera, however, highly complex evaluation software is required. Considerable effort is also required to provide illumination sufficient to achieve sharply focused images.
Capacitive sensors can be used to calculate the weights of the tablets or capsules passing by them without the need for direct contact. From this information it is possible to determine whether or not the tablets or capsules are intact. Capacitive sensors are sensitive to vibrations, however, and also to interfering electrical fields and to the moisture content of the tablets or capsules.